Option sets that VTAM implements

VTAM® implements the following conversation option sets:

Flush the LU's send buffer (101): Enables a transaction program to explicitly cause the LU to transmit any data in its SEND buffer, regardless of the amount of data in the buffer. Any of the APPCCMD macroinstructions that send data accept a QUALIFY value that forces data transmission through the network.
PREPARE_TO_RECEIVE (105): Enables an application program to change a half-duplex conversation state from SEND to RECEIVE and, at the same time, include the function of the FLUSH or CONFIRM verb. The APPCCMD CONTROL=PREPRCV macroinstructions implement this option set.
Receive immediate (106): Enables a transaction program to receive whatever information is available on a conversation without having to request posting of the conversation. The functions available through VTAM (including the VTAM receive-any function and asynchronous return after issuing an APPCCMD macroinstruction) largely negate any need for this option set.
Full-duplex and expedited data support (112): Enables a transaction program to allocate a full-duplex conversation. This option set also enables the transaction program to send and receive expedited data. Option sets 101, 110, 113, and 247 are required in addition to this option set for full-duplex support.
Nonblocking architecture (113): Enables support for nonblocking architecture. This option set provides enhancement for half-duplex conversations and provides the basic functions required to support full-duplex conversation architecture.
Queued allocation of a contention-winner session (201): Enables a local program to allocate a conversation to a remote program on a session for which the local LU must be the contention winner. It also enables a local program to queue the conversation request if no contention-winner session is available immediately.
Immediate allocation of a session (203): Enables a program to allocate a contention-winner session only if one is immediately available; otherwise, the allocation is unsuccessful. The application program issues the APPCCMD CONTROL=ALLOC, QUALIFY=IMMED macroinstruction.
Queued allocation for when session free (205): Enables a local program to allocate a conversation to a remote program on a session for which the local program waits for the duration of a session activation, if necessary. If session activation cannot be accomplished by the LU 6.2 application program, control is returned to the local program if activation fails. The application program issues the APPCCMD CONTROL=ALLOC, QUALIFY=WHENFREE macroinstruction.
Long locks (244): Enables a transaction program on a half-duplex conversation to issue a PREPARE_TO_RECEIVE verb, which includes the function of the CONFIRM verb, and to resume processing when data is subsequently received from the remote transaction program. The LOCKS=LONG keyword on the APPCCMD CONTROL=PREPRCV macroinstructions implement this option set.
Test for request to send received (245): Enables a transaction program on a half-duplex conversation to test whether a request-to-send notification has been received on a conversation (for example, following sync point processing).